/michael-pass.com

C	boot from cd or dvd
D	force the boot device to be the internal hard drive
T	start in firewire target disk mode – essentially turns your mac into a wicked expensive external hd
X	force boot into mac os x (older macs that dual-boot into os 9 and x)
N	boot from network drive
shift	hold after power-up to boot into safe mode, hold after login to prevent startup items from opening
mouse button	eject cd before booting normally
command-S	boot into single user mode; type exit when done
command-option-O-F	boot into the open firmware prompt
command-option-P-R	reset PRAM
command-option-V	verbose boot
command-option-shift-delete	bypass internal hard drive and boot from external drive or cd
option	shows the startup manager for all bootable drives
command-.	when startup disk chooser is active, open the cd tray

there are tons of guides out there on this topic. this is just here so i can get to it faster.

reset 10.5 leopard & 10.6 snow leopard password

1. power on or restart your mac.
2. at the grey screen hold down command+s on your keyboard to enter single-user mode
3. it’s a good idea because it checks the consistency of the hard disk before moving on. at the prompt, type fsck –fy and press enter. wait for the checks to complete before going to the next step.
4. type mount -uw / and press enter
5. type launchctl load /system/library/launchdaemons/com.apple.directoryservices.plist and press enter.
6. type dscl . -passwd /users/username password and replace “username” with one of the users displayed in the previous step. replace “password” with a new password of your choice. press enter.
7. reboot

 

reset 10.4 tiger password

1. power on or restart your mac
2. at the grey screen hold down command+s on your keyboard to enter single-user mode
3. type sh /etc/rc and press enter
4. type passwd username and replace “username” with the short name of the user account for which you’d like to reset the password
5. type your desired password and press enter
6. reboot